Residents 'Adopt' Vitthalwadi River Stretch, Hyacinth Cleared

A 1-km stretch of the Mutha river has been taken up for this project, and is visited by residents every Sunday to clean the water hyacinth; the weed is then layered with dry leaf litter and left for decomposing. Experts have cautioned that river pollution must not be allowed to seep into the soil in this way; PIC: NIKHIL GHORPADE

Residents join NGO to use this aquatic weed for composting with dry leaves, will try and use this manure to revive lost river flora during the monsoon

It has been years together that the people of Pune, activists and the authorities have strived to clean the city’s rivers of the choking weed — water hyacinth — that covers their surfaces. Unfortunately, this natural pollution finds its way back to the river each time, despite being removed and dumped outside the water, and multiplies manifold as well, feeding on the pollution and throttling resident biodiversity.

Now, offering a more permanent fix to this never-ending problem, the inhabitants of Vitthalwadi have along with the NGO Brown Leaf chanced upon an organic solution, which not only cleans the rivers but also utilises the hyacinth for a positive cause.

The initiative, which currently has around 35 area residents participating in it, has involved these citizens into ‘adopting’ a one-kilometre stretch along the Mutha River. The volunteers visit the site every Sunday to clear the hyacinth on the water, then dry it out as compost along with dried leaf litter, leaving both of them to decompose together along the banks.

Residents have been trained on how to alternate layers of dry leaves and aquatic plants for composting, and with each visit, over 10 kg of the hyacinth is being collected from the Mutha and layered outside.

Since water hyacinth is an aquatic plant, it cannot survive in soil and decomposes rapidly, providing nutrients to the earth. Once this composting is finished, in the rainy season, those who have adopted the stretch will be planting trees on the site to check if the soil quality has improved.

One such adopter, Hemant Pawar, shared, “My family and I were already regularly involved in river and riverbank cleaning drives — but after clearing hyacinth, these disposed plants used to just collect in heaps on the riverside. Some days ago, volunteers of this NGO conveyed to us the idea of composting the weed, which is an excellent concept. While we are sure this will positively impact soil quality, the tangible benefits will be visible for all once the plantations on top of these compost pits come through.”

Brown Leaf founder Aditi Deodhar, who began this project to convert water hyacinth into manure, explained, “Most people know that this water hyacinth is an invasive aquatic plant that is hazardous to the river and its aquatic life. By getting it out of the water body and embedding it in the soil with dry leaves, it cannot survive and rapidly speeds up the composting process. Plus, nutrients get fed directly into the ground.”

The main purpose of these compost pits is to boost the river flora that has long been exposed to pollution and indiscriminate removal. “We are trying to revive riparian vegetation, but last year, since the land was too rocky, none of our plantations survived. This year, we are quite sure that in the monsoon, if our plantation is done on this compost site, the possibility of survival will rise. Every species has an ecological check — meaning it is kept in control by some other species. In case of water hyacinth, only this weed was brought here, not the beetle that feeds on it.”

With no natural enemies, water hyacinth has grown unabated, thriving on the nitrates and phosphates in the water. Experts have said there are very few options to dispose of these plants in the correct manner.

Hydro-geologist and groundwater expert Upendra Dhonde told Mirror, “There are various ways in which water hyacinth can be utilised as manure and even food for some animals. Such efforts can prove useful, but some things must be taken care of. These aquatic plants feed on river pollution, so while converting them into manure, one must be careful that the toxins of the water or heavy metals do not in turn reflect on the soil quality.”